Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
98 words
A carbon fiber reinforced silicon nitride based nanocomposite material comprising: a nanocomposite material consisting essentially of at least one of a silicon nitride phase and a Si-Al-O-N phase as a matrix phase and carbon fibers as a dispersed phase, ultrafine, nanometer level particles of silicon carbide dispersed within crystal grains and at crystal grain boundaries of the matrix phase, the silicon carbide being present in an amount of 0.2 to 60 mole of the matrix phase, wherein at least a portion of the matrix phase is produced by thermally converting a preceramic polymer comprising mainly silicon and nitrogen.
Claim 2
Dependent Claim
98 words
A carbon fiber reinforced silicon nitride based nanocomposite material comprising: a nanocomposite material consisting essentially of at least one of a silicon nitride phase and a Si-Al-O-N phase as a matrix phase and carbon fibers as a dispersed phase, ultrafine, nanometer level particles of silicon carbide dispersed within crystal grains and at crystal grain boundaries of the matrix phase, the silicon carbide being present in an amount of 0.2 to 60 mole of the matrix phase, wherein at least a portion of the matrix phase is produced by thermally converting a preceramic polymer comprising mainly silicon and nitrogen.
Claim 3
Dependent Claim
30 words
The carbon fiber reinforced silicon nitride based nanocomposite material as defined in claim 1 wherein at least 5 vol% of the matrix phase has been derived from said preceramic polymer.
Claim 4
Dependent Claim
42 words
The carbon fiber reinforced silicon nitride based nanocomposite material as defined in claim 1 wherein the ultrafine particles of silicon carbide with a mean crystal grain size of 500 nm or less are dispersed within the crystal grains of the matrix phase.
Claim 5
Dependent Claim
42 words
The carbon fiber reinforced silicon nitride based nanocomposite material as defined in claim 3 wherein the ultrafine particles of silicon carbide dispersed at the crystal grain boundaries of the matrix phase have a mean crystal grain size of 2500 nm or less.
Claim 6
Dependent Claim
29 words
The carbon fiber reinforced silicon nitride based nanocomposite material as defined in claim 1 wherein the matrix phase has a mean crystal grain size of 0.3 to 30 μm.
Claim 7
Dependent Claim
36 words
The carbon fiber reinforced silicon nitride based nanocomposite material as defined in claim 1 comprising 20 to 80 wt% of at least one of silicon nitride and Si-Al-O-N based on the total weight of the material.
Claim 8
Dependent Claim
20 words
The carbon fiber reinforced silicon nitride based nanocomposite material as defined in claim 1 wherein the carbon fibers are filaments.
Claim 9
Dependent Claim
157 words
The carbon fiber reinforced silicon nitride based nanocomposite material as defined in claim 1 wherein said preceramic polymer is at least one selected from the group consisting of perhydropolysilazane, polysilazane and polyorganohydrosilazane, said perhydropolysilazane having a main repeating unit represented by the formula --Si H 2 N H) n , said polysilazane having a main repeating unit represented by the formula ##STR2## wherein R stands for a group having 7 or less carbon atoms selected from the class consisting of alkyl group, alkenyl group, aryl group, cycloalkyl group, alkylsilyl group, alkylamino group and alkoxy group, and said polyorganohydrosilazane having the formula (R 1 SiHNH)×[(R 2 SiH) 1 .5 N 1-x ], where R 1 and R 2 may be the same or different and represent a group having 7 or less carbon atoms selected from the class consisting of alkyl group, alkenyl group, aryl group, cycloalkyl group, alkylsilyl group alkylamino group and alkoxy group, and where 0.4<x<1.
Claim 10
Dependent Claim
39 words
The nanocomposite material as defined in claim 1 or 2 wherein the ultrafine particles of silicon carbide dispersed within the crystal grains of the matrix phase have a mean crystal grain size of about 10 nm to 200 nm.
Claim 11
Dependent Claim
37 words
The nanocomposite material as defined in claim 9 wherein the ultrafine particles of silicon carbide dispersed at the crystal grain boundaries of the matrix phase have a mean crystal grain size of about 300 nm or less.
Claim 12
Dependent Claim
27 words
The nanocomposite material as defined in claim 1 wherein the silicon carbide is present in an amount of 0.5 to 25 tool % of the matrix phase.
Claim 13
Dependent Claim
32 words
The nanocomposite material as defined in claim 10 wherein said at least one of silicon nitride and Si-Al-O-N is present in an amount of 40 to 65 wt% of the entire material.
Claim 14
Dependent Claim
26 words
The nanocomposite material as defined in claim 1 wherein the carbon fibers are present in an amount of 10 to 70 vol% of the entire material.
Claim 15
Dependent Claim
22 words
The nanocomposite material as defined in claim 1, which has a fracture toughness K rc of at least 18 MPam 1/2 .
Claim 16
Dependent Claim
22 words
The nanocomposite material as defined in claim 1, which has a fracture toughness K rc of at least 23.5 MPam.sup. 1/2 .
Claim 17
Dependent Claim
22 words
The nanocomposite material as defined in claim 1, which has a fracture toughness K rc of at least 30 MPam 1/2 .
Claim 18
Dependent Claim
22 words
The nanocomposite material as defined in claim 1, which has a fracture toughness K rc of at least 32 MPam 1/2 .